Pivotal to Canterbury's eighth success in nine matches were the assured performances of inside backs Andy Ellis and Stephen Brett in Christchurch.

Both have been spelled by injury for periods this season but both showed they are returning to their sharpest form.

Halfback Ellis ducked in for a brace of first-half tries while first five-eighth Brett was an influential figure in wet conditions.

He made the decisive midfield burst leading to Ellis' first try, then set up Canterbury's third try before the break when a well weighted grubber kick inside the Hawke's Bay 22 sat up invitingly for second five-eighth Tim Bateman.

Brett then rubbed Hawke's Bay's noses in it when he casually knocked over a dropped goal seconds from the interval to give Canterbury a commanding 24-7 advantage at the break.

The result ensured Canterbury will finish second behind Wellington when the round robin draws to a close next weekend.

Hawke's Bay stay third but now need to win their remaining game against Bay of Plenty next Friday to confirm they retain that position entering the quarterfinals.

Canterbury had to make do without Brett for most of the second half after he was substituted off shortly after the restart when he appeared to take a knock in a tackle.

The match had started promisingly for Hawke's Bay, who grabbed an early 7-0 lead after left wing Zac Guildford scored a try when he ran on to a cross kick and toed the ball ahead over the line.

But Canterbury took control after that, with Ellis and Brett guiding the side effectively in conditions that made ball control difficult.

The second half degenerated as a slippery ball and pressure in the tackle meant turnovers were plentiful.

Canterbury continued to dominate in the territorial stakes but it was not until the last minute that they made it count, with replacement flanker George Whitelock capping off a a long-range counter-attack to earn them a bonus point for scoring four tries.